title: DNA assembly and enzymatic cutting in solutions: a gold nanoparticle based SERS detection strategy.
abstract: The ability to monitor biomolecular recognition such as DNA hybridization and enzymatic reactivity in solutions with high sensitivity is important for developing effective bioassay strategies. Surface enhanced Raman scattering (SERS) based on use of solid substrates to produce the SERS effect for the detection often requires substrate preparation which is ineffective for rapid monitoring. This report describes a new strategy exploiting a gold nanoparticle (AuNP) based interparticle "hot-spot" for SERS monitoring of DNA mediated assembly and enzyme induced cleavage of the assembly in solution phase. The DNAs consist of two different complementary DNA strands with a thiol modification for attachment to AuNPs of selected sizes. In a solution containing AuNPs conjugated with one of the single-stranded (ss) DNA and other AuNPs labeled with a Raman reporter molecule, 4-mercaptobenzoic acid (MBA), the introduction of the complementary DNA strand leads to a linkage of the two types of AuNPs, producing double-stranded (ds) DNA-AuNP assembly (ds-DNA-AuNPs) with an interparticle "hot-spot" for SERS detection of the diagnostic bands of the reporter. Upon introducing a restriction enzyme (e.g. MspI) into the ds-DNA-AuNP assembly solution, the removal of the interparticle "hot-spot" due to restriction enzyme cleavage of the ds-DNA leads to a decrease of the SERS signals. While the detailed cleavage process may depend on the reaction time and the amount of enzyme, the viability of using gold nanoparticle "hot-spot" based SERS monitoring of DNA assembly and enzyme cleavage is clearly demonstrated, which has important implications for developing new strategies for bioassays.
authors.affiliation: Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Crew
authors.forename: Hong
authors.initials: H
authors.lastname: Yan
authors.forename: Liqin
authors.initials: L
authors.lastname: Lin
authors.forename: Jun
authors.initials: J
authors.lastname: Yin
authors.forename: Zakiya
authors.initials: Z
authors.lastname: Skeete
authors.forename: Timur
authors.initials: T
authors.lastname: Kotlyar
authors.forename: Nuri
authors.initials: N
authors.lastname: Tchah
authors.forename: Jehwan
authors.initials: J
authors.lastname: Lee
authors.forename: Michael
authors.initials: M
authors.lastname: Bellavia
authors.forename: Isaac
authors.initials: I
authors.lastname: Goodshaw
authors.forename: Pharrah
authors.initials: P
authors.lastname: Joseph
authors.forename: Jin
authors.initials: J
authors.lastname: Luo
authors.forename: Susannah
authors.initials: S
authors.lastname: Gal
authors.forename: Chuan-Jian
authors.initials: CJ
authors.lastname: Zhong
mesh_terms: D001483:Base Sequence; D001565:Benzoates / Q000737:chemistry; D004247:DNA / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D053837:DNA Cleavage; D019003:Deoxyribonuclease HpaII / Q000378:metabolism*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D009693:Nucleic Acid Hybridization; D012996:Solutions; D013059:Spectrum Analysis, Raman; D013438:Sulfhydryl Compounds / Q000737:chemistry; D013499:Surface Properties
chemical_list: D001565:Benzoates; D012996:Solutions; D013438:Sulfhydryl Compounds; C013594:4-mercaptobenzoate; D006046:Gold; D004247:DNA; D019003:Deoxyribonuclease HpaII